C1512 Diagnostic Trouble Code

C1512 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a C1512 diagnostic trouble code may include:

Poor acceleration
Cherry red hot catalytic converter
Possible spark knock (detonation / pre-ignition)
Reduction in engine performance, especially at low RPM levels

Possible Causes :

A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.
Some aftermarket accessories and performance modifications
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.

Repair Processes :

With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Use the DVOM to test resistance and continuity on all system circuits if actuator and sensor resistance levels are in compliance with manufacturer's specifications. Look at the plug wires to make sure they are not burnt or laying on the exhaust.

Process Tips

Diagnostic trouble code C1512 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before C1512.

Fortunately, C1512 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C1512 Trouble Code For Specific Cars

C1512 Leidart V-8 TCM Communication Circuit Range/Performance
C1512 Citroen Six Fuel Pump Secondary Circuit Low, High Speed
C1512 Nash Ambassador Catalyst System Efficiency Below Threshold (Bank 2)
C1512 Buick Cielo Cylinder 6 Misfire Detected
C1512 Denzel Wd Hydraulic Pump Relay Circuit Failure
C1512 Tvr 400 Power Door Lock Circuit Open
C1512 Ferrari 599 Intake Valve Control Solenoid Circuit (Bank 2)